Make layer_selector node IDs deterministic.

Using a static int to generate uniqueIDs for nodes is problematic
when nodes load in a different order. To make node IDs deterministic
we derive them from the text value and their position in the tree.
Replace deprecated event in feature compare plugin.

The ArcGIS API 'update' event was deprecated in v2.0 and replaced with
'update-start' and 'update-end'. Features seem to load more consistently
using the 'update-end' event.
Clean up script/css imports

While poking around for the Foundation version (it's 3), I realized the
foundation.js we pull into the project has a version of jQuery and
Modernizr bundled into it.  It appeared that those were the versions
that we ultimately referenced on the page, so I removed the duplicate
declarations.  Presumably, this is not an ideal situation but I think it
should be resolved in a larger script issue (minifiying/concat).
Add dropdown menu plugin

The version of foundation we are using does have a dropdown component
so I added a small jQuery plugin for the functionality required for the
menu
dropdown feature.
Update region schema for menu header links

There is some new duplication with specifying the content of
header link menu items, which are also header links.  This
json is consumed server side and I did not want to attempt
JS execution to dynamically produce the result, as we've done
for some plugin schemas.
Add dropdown menu option for header links

To support the CoastalResilience feature of a configurable "Go To..."
link which will allow users to navigate between different C.R. regions,
I added this general purpose drop down link.  It does not support
nested dropdowns, as it was more compliated and the original feature
wasn't requesting it.
Merge pull request #219 from kdeloach/topic/share-save-fix

Fix some issues with save/share
Merge pull request #220 from mmcfarland/topic/dropdown-menue-control

Dropdown menu control for header links
Remove use of reserved keyword `export`

`export` is a future reserved keyword and IE8 fails execute
javascript which uses it as an identifier.  Since our region.json
becomes a javascript object, I changed the setting value to a
benign word, and IE8 works "great".
Merge pull request #221 from mmcfarland/bugfix/ie8-reserved

Remove use of reserved keyword `export`